I bought my boy a 97 Z34 that needed the tensioner pulley (and cam pulleys) replaced. Yhe car came with a new serp belt and three pulleys but from what I can tell the pulley seized and disintegrated. Likely throwing the timing off in the process but I cant tell. Should i be concerned with internal damage? The car is mint outside and only cost us $1000. Bought it from a guy who bought it from his friend that was the original owner and the one that had it when the pulley went.

 

Unfortunately on a twin cam Z34 when the timing belt goes it almost always takes out the valves in the head. It turns into a very expensive repair. Wish I had a better answer. Good luck

 

...even in a non-interference engine? I have never owned one of these engines so I looked it up and found that it is a non-interference engine which gave me some hope.. but it sounds like that's not the case.

 

did another search on this engine..I was wrong. The LA1 is an interference engine. Apparently some 3.4L are not.
What tell-tale signs of bent valves will I encounter? Knocking..etc?
should I just change the heads out regardless?

 

IT ain't over tell its over? here is a link to some your tube stuff about this car. check it out. I know a fellow who had a similar issue on a 95 and got it all fixed. Each year they improved some stuff on this engine you maybe okay.

https://www.youtube.com/results?sear...V6+TIMING+BELT

 

If you're concerned that it hit, maybe you could pick up one of of those cheap bore scopes off Amazon to look at the pistons? Or you could just pop off the heads and use it as an excuse to refresh the gaskets (assuming it isnt trashed).

 

...I suppose eh. The gaskets are an issue on these engine too right...

 

Any tips or tricks to get the intake plenum off this thing? Can't get to the bottom bolt on the elbow to release it from the tubing. Can get the other two out not that third one.

 

I dont know how similar it is to a 3.8, but I think they are pretty close, I've been doing a top end on mine, my plenum was blown to pieces when I got it, so I'm not sure to which bolt you are referring to, however a few bolts I had a hard time with until I discovered you can remove the tube frame supports with no risk , and also if you remove the steel motor mounts above the radiator, you can shift the engine quite a bit toward front or rear, kind of a spin if you will, and this aids with access to many things. It will spin more with the exhaust off.

The job shouldn't be too expensive, valves are $10-$15 each on Rock Auto and pretty much everything you need you can get from them and far more reasonable than parts from parts stores. Be aware though, "pay attention to the shipping" many of the items can ship from different warehouses increasing the costs, but often the same item can be obtained from other warehouses than the part you originally choose, but its still more competitive than driving down to the local discount auto.

Getting the front head and exhaust off wont be too bad, the rear one will be a bit aggravating, to make it easier having about 2ft of extention bar with the Socket ends being the curved type which will get you a little bow with the extentions. Some of the exhaust bolts have a square head about the same size as the bolt, and even though there is a nut on it, You might have to remove it by clamping vise grips on the square head.

Tool list to make the whole job easier : Going to Harbor Freight, you can get everything you need on a budget, 20% coupons off, and free stuff !
1st: get a 1/2 drive ratchet with the expandable handle, You can extend the handle and really get the leverage when you need it, well worth the money, and its not much money! They have both 1/2 ft/lb torque wrenches, and 1/4 drive in/lb torque wrenches for like $20 each, a flex handle ratchet, while not user friendly will come in handy in a couple instances. A metric set of deep well sockets, and if you have cordless drills, or corded drills, they have a kit with 3 socket bits, 1/4, 3/8, 1/2, that can seriously speed up your time.
You will probably need a valve lapping tool, and valve grinding compound. I found I could pull the suction cup off the hand lap tool and squeeze it into a socket and brzzzz it with the cordless. The grinding compound will get under the suction cup though.

You'll have fun , and probably like me, want to do more than you intended. :-))

 

have a line on a 3.8L from a 2002MC. anybody know if those heads are a direct swap?